Environmental Proteomic Analysis in a Contaminated Aquifer: From Column to Field- Scale

Column flow-through cells packed with sediment material from a uranium-contaminated site (Rifle, CO) were operated under environmentally relevant conditions. Iron-sulfide and calcite precipitation was observed in column effluent tubing whilst subsequent SEM analysis of the tubing revealed the presence of large numbers of microorganisms. Column effluent tubing was removed, flash-frozen and the recovered biomass analyzed using proteomic techniques. Following the successful extraction of protein from the tubing, 2D-LC-MS/MS results revealed that the gram-negative bacterium Dechloromonas aromatica was present in the tubing community. Out of 2710 unique peptides identified in the sample, 1814 matched this species, indicating that it may play an important role in these biofilms. Similar darkening of pump tubing has been observed in field scale bioremediation projects at the Rifle site, whilst 16S rRNA techniques were used to identify D. aromatica playing an important role in a selenium-bioremediation process occurring in the same tubing. This data demonstrates that the proteomic analysis of column-based material may be useful when attempting to scale-up to field-based proteomic studies.